Telephone-exchange system



April 5 Q 1927.

s. a. WILLIAMS ET AL TELEPHONE EXCHANGE SYSTEM Filed Ma o-h 29, 1924 s sheets-sheet 1 &

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April 5, 1927.

s. B. WILLIAMS ET A1,

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I 1,623,769 UNITED, STATES PATENT tors lQE.

,sAMUEL B. WILLIAMS, or BROOKLYN, YORK, Ann EARL s. GIBSON, or RIDGE- woon, NEW JERSEY, ASSIGNORS T0 WESTERN ELEcTRIc COMPANY, INCORPO- RATED, or NEW YORK, N. Y.,

A CORPORATION OF NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

Application filed March 29, 1924. Serial No. 792,732.

. This invention relates to a telephone exchange system and more particularly to telephone exchange systems in Which connections are established by automatic switches under the control of a calling subscriber.

Anobject of this invention is to provide in an automatic telephone exchange system of large capacity an improved call charging system arranged to utilize a minimum ofcentral oifice apparatus which will operate efiiciently.

A feature of this invention consists in providing a sender mechanism commonly available to calling subscribers lines either equipped or not equipped with coin box mechanism for controlling the establishmentof a connection to a called subscribers line and arranged to arrest the establishment of the connection when the call originates on a coin subscribers line until after the deposit of a coin in the coin box asso-. ciated' with the calling subscribers line.

Anotherfeature of this invention consists in providing means individual to each district selector switch associated with the calling subscribers lines equipped with coin box mechanism, for causing a sender mechanism .normally arranged to function on a non-coin basis tofunction on a coin basis when associated with such a calling subscribers, line. It is understood that this feature of the invention is not limited to lines equipped with charging means actuated by the deposit of a coin but it may be used with calling subscribers lines equipped with various kinds of charging means such as a subscribers charge meter similar to the coin box mechanism herein disclosed and actuated by the pressing of a. key instead of the deposit of a coin.

Still another feature consists in providing a minimum number of coin control circuits commonlyavailable to any of a plurality of sender mechanisms. anyone of which latter may be employedto associate a coin control circuit witha calling subscribers line. V

' A. further feature of this invention consists in providing a call charging system wherein an idle one of a plurality of coin control circuits commonly available to a plurality of calling subscribers coin lines is connectedto a calling subscribers coin line by meaus of one of a plurality of sender mechanisms before theestablishmentof the talking connection and an idle one of said plurality of said coin control circuits is connected to one of said calling subscribers coin lines after the disestablishment of the talking connection by means of a simple coin circuit instead of a complicated ender mechanism.

still further feature of this invention consists in providing a sender selector switch common to the calling subscribers coin and non-coin lines arranged to select a sender mechanism for the purpose of controlling the establishment of a talking connection and to select arspecial coin circuit upon the disestablishment of the talking connection when the calling line used is provided with a coin box. f

Various other novel features will be observed from a consideration of the followingdescription of this system taken in connection with the appended drawings.

The upper portion of Fig. 1 represents a line switch 25 arranged to exclusively connect the calling subscribers coin line 10 to a district selector. switch. circuit arranged for coin service, such as shown at 100 in Fig. 2. The lower portion of Fig. 1 represents the line switch 50 arranged to connect non-coin subscribers station 20 to a district selector switch circuit arranged for non-coin service such as shown at 150 in Fig. 2. j

In the upper portion of Fig. 2 a district selector switch circuit arranged for coin service is disclosed in part at .100. In the lower portion of Fig. 2, represented by numeral 150, a districtselector switch circuit arranged for non-coin service is partially disclosed.

3 and 4 takentogether represent a sender selectorarranged to select either a recording senderor a coin control connect-- ing circuit.

Fig. 5 illustrates a portion of a recording sender 400 of substantially the same type as the recording sender illustrated and described in the patent to S. 'B. WVilliams, No. 1,517,331, granted Dec.;2, 1925, including in schematic form only such portions of the circuit as are necessary to an understanding of this invention.

, It will be observed that certain of'the apparatus 1n thisfigure, necessarily shown to function witty-that portion of the sender. i

volved in this invention, bears the same indicating numerals as borne by similarly operating apparatus in the aforesaid patent. Thelower portion of Fig. 5 indicated by numeral-450 represents a pecial coin sender containing a minimum amount of apparatus arranged to be connected only to calling subscribers lines equipped with coin boxes in the place of the complicated recording sender 100 for the purpose of col lecting or. returning a coin after the termination of a successful connection to the called subscribers line.

Fig. Grepresents a coin control connector arranged to connect an idle one of a plurality of coin control circuits to one of a plurality of either recording senders or special coin senders.

Fig. 7 represents a coin control circuit arranged to control the recording sender and the disposition of a coin inserted in the coin box of a coin subscribers line.

Fig. 8 shows diagrammatically a district switch in which the district circuit of Fig. 2 terminate, a connector switch and subscribers lines terminating in the connector switch.

In a system of this nature, a coin subscribers line terminates in a line switch, the trunks outgoing from which terminate eX- clusively in district selector switehcircuits arranged-for coin service. A non-coin subscribers line terminates in a line switch, the trunks outgoing from which terminate exclusively in district selector switch circuits arranged for non-coin service. Both the coin and non-coin service district selector switch circuits have access to a common district selector switch which extends a connection to the called party through a subsequent train of switches in the same manner as described in the patent to S. B. Villiams. No. 1,517,331, granted Dec. 2, 1924.

It is thought that the invention will be bestunderstood from a detail consideration of the circuits disclosed and the manner in which they function. It will first be as sumed that a subscriber whose line 10 is equipped with acoin box initiates a call by removing his receiver from the switchhook.

lVheu the subscriber takes the receiver from the hook at substation 10. the vertical magnets 1 and 6 are operated and the leads 8 and 9 from substation 10 are connected by conductors 12 and 13 to coin district selector circuit 100 in a manner well known in the art anddescribcdin the patent to S. B. YVilliams, No. 1,517,331.

Vertical magnet 6 in operating completes a circuit from ground on the front contact of magnet 6, conductor 11. conductor 121, conductor 122, back contact of slow release relay 102. conductor 123, winding of relay 201, conductor 221 to battery through the winding of relay 311. Relays 201 and 311 operate in this circuit. Relay 201 in operating provides a locking circuit for itself and relay 311, through its inner left front contact, conductor 12 1, inner right-back contact of relay 101 "to ground over conductor 11. Relay 201 in operating completes a circuit from battery, winding of slow release relay 102, conductor 125 to ground on its outer left front contact. Relay 102 operates and at its left front contact provides a circuit over conductor 11 for maintaining the line switch 25 operated after the line switch vertical magnets 1 and 6 are restored in the manner described in the aforesaid patent to S. B. \Villiams. Relay 102 in operating also opens the initial energizing circuit of relay 201.

Relay 311 in operating causes the sender selector to connect an idle sender to the coin district selector circuit 100 in the following manner: at its front contact relay 311 closes an obvious circuit for operating relay 313. Relay 313 operates and closes a circuit from battery. winding of relay 215, conductor 220 to ground on the left front contact of relay 313, operating relay 215. Relay 313 at its right front contact closes a circuit for operating group relay 314-, from battery, left winding of relay 314. right front contact of relay 313. conductor 227. inner back contact of relay 225 to ground on the inner back contact of relay 224. Relay 314- in operating completes at its outer right front contact an obvious circuit for operating relay 312. Relay 312 operates locks over its right contact. conductor 231. inner left contact of relay 215 to ground at the contact of relay 222, and at its left back contact opens the energizing circuit for relay 313 which dcencrgizes.

lVhen relay 314 operates it completes a circuit for holding itself energized and for operating relay 225, prior to the decuergiz. tion of relay 313. from battery. through its right winding and inner right. front contact. conductor 220. winding of relay to ground on the inner back contact of relay 224. The operation of relays 31-1: and 225 by holding open the energizing circuits of all other vertical group relays similar to relay 304- at either the inner right back coni-act'of relay 31s or at the back contact of relay 225 iwcvcnts the possibility of any other calling line associated with any other vertical group from attaching itself to a sender. lVith relays 314 and operated. a circuit is completed from battery. winding of multi-contact relay 223. lead 230. outer left front contact of relay 314. conductor 223. inner right front contact of relay 225 to ground at the inner back contact of relay 224. Relay 223 operates but performs no useful function at this time.

When relay 313 dcenergizes it opens the initial energizing circuit of relay 314 and inn tbe energizing circuit for relay 215. Relay 215 doesnot release due to the operation of relay 312, providing a holding circuit for relay 215 before relay 313 can release from battery, winding of relay 215, conductor 226, left front contact of relay 312 to ground on the front contact of relay 311. The reoperation of relay 215 provides a locking circuit for relay 312, traceable from battery, winding and right front contact of relay 312, conductor 231, front contact of relay 215 to ground at the back contact of relay 222 c The continued operation of relay 312 by holding open the energizing circuit for rc lay 313 at its back contact, prevents at this time the possibility of any other district selector circuit in the same vertical group as district selector 100 from being connected tal group relay,

relay to an idlesender.

' lVhen relays 314 and 225 are operated, a circuit is completed for operating sender Vertical magnet 325. This circuit may be traced from battery, winding of vertical magnet 325, inner left frontcontact of relay 314, conductor 228, inner front contact of relay 225 to ground at the back contact of relay 224. Magnet 325 operates and rotates its'associated'vertical rod to prepare the switch contacts of all lines common to verti cal magnet 325 for connection with a horizontal link.

Relays 314 and 225 in operating also complete a circuit for operating an idle horizon- .such as relay 210, in circuit which may be traced from battery, right winding ofrelay 210, outer right front contact of relay 201, back contact of relay 214, conductor'233, middle right front contact of 314, conductor 228, front contact of re lay 225 to ground on the back contact of relay 224. Relay 210 operates and completes a locking circuit for itself from battery, through its left winding and inner left front contact, the left inner back contacts of other horizontal group relays 211 and212 in series, winding of relay 214, conductor 233 to ground, as previously described. Relay 21a ope ates in this circuit and attracts its armature, opening the initial energizing cir cuits of all horizontal group relays thereby preventing the operation at this timeof a horizontal magnet in any horizontal group other than in the horizontal group associated with and controlled by horizontalgroup relay 210. Relay 210in operatingalso closes at its outer left front contact an obvious circuit for operating relay 207. Relays 223 and 207 which are operated perform no useful function at this time.

a When relay 225 Was firstoperated, a circuitwas completed from battry, winding of slow release relay 213, outer right front contact of relay 225 to ground at the outer rightback contact of relay 224. Relay 213 .front contact holding operates and in so doing provides an additional holding circuit for relays .314 and the front contact of sender vertical magnet 325. Trunk vertical magnet-336 operates and rotates its associated vertical rod to prepare the contacts of all outgoing trunks asso ciated with trunk vertical magnet 336 for connection to a horizontal link.

When trunk vertical magnet 336' operates, a circuit is completed for operating relay 224. This circuit may be traced from battery, winding of relay 224, conductor 234 to ground on the'innermost front contact of magnet 336, Relay 224 in operating opens the energizing circuit of slow release relay 213. The slow release relay is so constructed as .to release so slowly as to provide on its ground for relay 225 for a sufficient length of time after the operation of relay 224 to assure the operation of the first idle horizontal magnet in the group of horizontal magnets controlled by horizontal group relay210.

The first idle horizontal magnet 306 operates in a circuit from battery, rightwinding of horizontal magnet 306, back contact of horizontal relay 217, right front contact of horizontal group relay 210, right back contacts of other horizontal group relays in series, conductor 235, lower front cont-act of sender vertical magnet325 to ground on the middle front contact of vertical magnet 336. Horizontal magnet 306 in operating rotates its associated horizontal rod 370 so as to connect the conductors of the horizontal link 375 with the contacts terminating in circuit connector 260 and with the contacts of register .sender connecting circuit 351, thereby connectingv district selector circuit 100 to the recording sender 400;

Relay 224in operating opens-the initial holding circuit for energizing relays 314 and 225 at its innermost back contact. Consequently, when relay 213 fully releases the energizing circuit through the right winding of relay 314 and the winding of relay 225 is opened at the front contact of relay 213, thereby releasing relays 225 and 314. Relay 314 in deenergizing opens the circuit for operating sender vertical magnet which releases. Sender vertical magnet 325 in releasing opens the operating circuit of trunk vertical magnet 336 causing it to release, Relay 314 in releasing also opens the energizing circuits ofrelays 210., 214 and 223 causing them to release. Sender vertical releasing in turn releases re magnet 336 in lay 224. Relay 224 in releasing completes a circuit from battery winding of relay 222 outer left front contact of relay 213, conductor 237, back contact of relay 303, back contact of relay 313, conductor 227 back contact of relay 225 to ground on the back contact of relay 22f. Relay 222 operates and at its backcontaet opens the holding circuit of relay 312 which releases and in turn releases relay 215. Relay 215 in releasing opens at its outer front contact the energizing current of relay 222 causing it? to release. It is to be noted that all relays controlling the operation of the vertical magnet are now released.

Immediately upon the operation of horizontal magnet 306 connecting the district selector circuit 100 to the sender 100, a circuit is completed for operating pulsing relay 101 of the senderfrom battery, right winding of pulsing relay 101, outer left back contact of relay 404:, inner right back contact of relay 420, inner right back contact of relay 4103, conductor H1, contacts and conductor of horizontal link 375 of switch 300, conductor 358, conductor 13, contacts and horizontal link of line switch 25, conductor 0, substation 10, conductor 8, contacts and horizontal link of line switch 25, conductor 12, conductor 357, contacts and conductor of link 375 of sender selector switch 300, conductor 1 12, outer right back contact of relay 403, outer right back contact of'relay 4-20, innermost back contact of relay 104; to ground through the right winding of re tardation coil 402. Relay 4.01 operates in this circuit and completes at its front contact an obvious circuit for operating slow release relay 123. Relay 423 in operating completes at its outer right front contact an obvious circuit for operating relay 421. Relay 4:21 in operating completes a circuit for holding horizontal magnet 306 operated after thedeenergization of sender vertical magnet 336, traceable from battery, windings of horizontal magnet 300, winding 0 relay 217, contacts and horizontal link conductor 375 of sender selector switch 300, conductor 145, left inner back contact of relay 4.03 to ground on the inner left front contact of relay 4:21. Relay 217 does not immediately operate in this circuit but waits until after relay 210 releases and opens the shunt circuit around the left" winding of relay 306 and the winding of relay 217;

lii accordance with the structure of'sendcr selector switch as describcdin the aforesaid patent to S. B. \Villiams, No. 1,517,331. while the horizontal magnet 306 is operated the district selector switch-circuit 100 will be held connected to the sender 400 despite the release of vertical magnets 325 and 330. The release of vertical magnets 325 and 336 restore their associated vertical rods to normal.

Upon the operation of trunk vertical magnet 336 a circuit is completed for operating relay 101 from battery, winding of relay 101, conductor 359, contacts and conductor of link 375 of sender selector switch 300, conductor 4 15 to ground on the lowermost front contact of trunk vertical magnet 330. Upon the operation of relay 101 ground on the inner left front contact of relay 421 is connected to conductor thereby providing holding ground for holding relay 101 operated when trunk vertical magnet; 330 releases. \Vith relay 101 operated a circuit; is completed for operating slow release relay 112 from battery, winding: of relay 112, outer left back contact of relay 111. outer right front contact of relay 101 to ground on the front Contact of relay 102. Relay 101 in operating opens at its inner right back contact the holding circuit for relays 201 and 311 causing these relays to release. Relay 201 in deenergizing opens at its outer left front contact the operating circuit for slow release relay 102. However, since relay 102 is slow 'eleasing, relay 112 will operate and complete an obvious circuit for energizing relay 102 before it can release in order to keep ground continuously on lead 11 for holding the line switch operated.

The sender involved in this invention is normally arranged forflat-rate service and when so arranged proceeds to control the establishment of a desired connection in the manner described in the patent to S. B. Villiams, No. 1,517,331, except that the circuit for connecting a line marker (not shown) to the sender is modified to the extent that the circuit is traced through the back contacts of several relays which are not shown in the sender of the above mentioned patent and which energize only when a coin line is calling.

lVhen it is desired to-use the selector for coin subscribers calling lines ground 2 10 is connectedto the inner right front contact of relay 201 of each coin district selector circuit associated with the calling coin lines. As will hereinafter be explained ground on the inner right front contact of relay- 201 operates a relay in the sender 300 causing the establishment of the talking connection to be arrested until after a satisfactory preliminary test for a coin in the calling coin snbscribers coin box has been madcf \Vhcn the sender is connected to the calling line, a circuit is completed before relay 201 releases from ground 210 on the inner front contact of relay 201, conductor 354, contacts and conductor of horizontal link 375 of sender selector 300, conductor 443, inner back contact of relay 105 to battery through the left winding of relay 407. Relay 407 operates andcompletes a locking circuit for itself through its right Winding and right front contact to ground on the middle right front contact of relay 4:21.

' operation of relay only as the result of a satisfactory prelim-.

dial tone in the well sender register. relays same manner as descrlbed and illustrated ground to lead 1451,

Relay 407 operates and attracts its left armature holding open the circuit for-operatingfthe line marker sender connector (not shown) thereby arrestingthe establishment of the talking connection until after the 411 which is operated inary coin test. s i V When the/sender is connected to the call ing line, the calling subscriber receives a known manner notifyinghim that the sender is ready to receive therdial pulses." The subscriber thereupon dials and the pulses are registered on'the 1n the aforesaid patent to S. B. l/Villiams.

When the thousands series of impulses are registered, thousand series register relay 808 is operated. as describedin said above mentioned patent and relay405 isoperated in a circuit from battery, winding of relay 405, front contact of relay 808 to. ground on the outer leftfront contact of holding relay 421.; Relay 405 in operating completes a circuit for operating a sender connector. A district marker is then attached to the sender and district selection is accomplished, where upon the district marker and the sender connector are released. The operation of the foregoing switches, only certain ones of whichare diagrammatically shown, is illus trated and described in detail in the aforesaid patent of S. B. WVilliains. .A description of the operation of the foregoing switches is not believed to be essential to an understandingof this invention and hence no description is given in this application. The release of the district marker,- as described in said foregoing patent, connects Fig. 5, thereby completing a circuit for operating relay 425. When the unit series of impulses are registered, control relay 927, Fig. 5, of the units register relays is operated, as described in I the aforesaid patent.

7 Preliminary coin teste-l3efore the sender may proceed any further in establishing the connection, it is necessary that a preliminary com test he made in thesender to ascertain 7 whether the subscriber has deposited the proper coin in the coin slot. Assuming that the sender is completing a local connection which'does not involvethe operation of class control relays, a circuit is closed at this time foroperating relay 404 from battery, winding of relay 404, inner left back contact of relay 411, left front contact of relay 407, back contact of relay 427, back contact of relay 410, back contact'of relay 409, back if contact of relay 418, front contact of relay 425, back contact of relay 424, front contact of units register control relay 927, outer left back contact of relay 403, to ground on the inner left front contact of relay 421.

(not shown) in the.

front contact of relay 404 to ground on the middle right front contact of 'holdingrelay 421'. The operation of relay 404 also completes a circuit for energizing the start relay 502 of the coin control connector switch 500. The start relays of the coin control connector switch 500 are arranged in a number of groups, group G, comprising start relays 502 and 503 and group G, comprisingstart relays 532 and 533. The senders in an exchange are divided into groups corresponding in number with the number of groups of start relays, each sponds to a particular group ofv start relays and each sender in a group is arranged to control the operation of a particular start relay of a corresponding group of start relays. V

Associated with each start relay is a sender vertical relay such as'506 and atrunk vertical relay such as 509 for connecting a control circuit to the sender associated with start relay 502. Each control circuit is preferentially common to all the senders in the exchange in accordance with the busy condition of its adjacent trunk vertical'relays as will be described hereinafter.

'With relay 404 operated the circuit for startrelay 502 may be traced from ground on the right front contact of relay 404, conductor 530, right winding of relay 502 through the left back contact of relay 501 to battery. Relay 502 energizes in the foregoing circuit and completes a locking circuit for itself from battery, winding of relay 501, left front contact and left winding relay 502, conductor 530, to ground on the right front contact of relay 404. Relay 501 energizes in this circuit and at its right front contact completes a circuit for operating sender multi-contact relay 506 and control relay 521. These relays are operated in circuits respectively from battery, through the winding of relay 506,,the inner right front contact of relay 502 to ground on the front contact of relay 501 and from bat-' "than one sender multi-contact relay in that group at one time. Multi-contact relay 506 operating group of senders correoperates and connectsthe leads terminating on its contacts to the conductors of the horizontal link 560.

"When relay 521 operates, it completes a locking circuit for itself from battery, winding of relay 52.3, the inner left front contact and left winding of relay 521 to ground on the front contact of relay 501. Relay 523 operates in this circuit and completes a circuit for operating coin control multi-contact relay 509 in a circuit from battery, through the winding of multi-contact relay 509, outer left front contact of relay 521 to ground on the front contact of relay 523. Coin control multi-contact magnet 509 operates and connects the sender associated with the calling subscribers line to the link 580 of the coin control circuit 600.

The coin control connector is so arranged that when a sender associated with one coin control connector group is connected to a coin control circuit no other sender associated with that particular group may haveaccess to a coin control circuit until the preliminary coin test for the first sender has been accomplished and relay 501 is deenergized. Thisis provided for by operating and locking in series relay 501 and the start relay such as 502 of whatever sender of a particular group of senders is connected to a coin control circuit connector, whereby battery potential is disconnected from the energizing circuits of all other start relays in that particular coin connector group.

In a similar manner, the coin control connector is arranged to prevent the operation at one time of more than one coin control multi-contact relay associated with any particular coin control circuit. This is accomplished by operatinga non-interfering relay, such 523, which attracts its left armature and disconnects battery potential from the energizing windings of all relays similar to521 associated with the coin control circuit connected to link 580.

If while the sender associated with start relay 502 is connected to the coin control circuit 600 start relay 532 should operate and attempt to connect its associate sender with the coin control circuit 600 already connected to the sender associated with sender 400 it would be prevented from so doing by reason of relay 523 having been operated as aresult of the operation of relay 521. The sender associated with start relay 532, however, will be connected to the coin control circuit connected to link 590. This is accomplished in the following manner:

When relay 523 operates, an obvious circuit isclosed t'or energizing relay 552. Relay 552 operates and closes a circuit at its front contact for operating control relay 54-1 from battery back contact of relay 513, right winding of relay 5&1, right back contact ot relay 542 right back contact of relay 533, right back contact of relay 551, front contact of relay 552, outer right front contact of relay to ground on the front contact of relay 531. Relay 541 operates and coinpletes a locking'circuit for itself from battery, winding of relay 513, inner left back contact of relay 511, inner left front contact and left winding of relay 541 to ground on the front contact of relay 531. Relay 513 operates in this circuit and byattracting its left-armature prevents the operation of all other control relays similar to relay 5 1 1 associatedwith the coin control circuit connected to link 590. lVhen relay 541 operates, it completes a circuit for operating multi-contact relay 538 from battery, winding of relay 538, outer left front contact of relay 541 toground on the front contact of relay 513. Relay 538 in operating connects the coin control circuit connected to link 590 to a sender in the same manner as described when relay 509 was operated.

At any time, any coin control circuit may be removed from the operation by depressing a make busy key individual to each coin control circuit and similar to key 510. For example, if for anyreason itshould be desired to remove from operation the coin control circuit connected to link 580, it may be done by depressing key 510. An obvious circuit is then completed for operating .relays 552 and 522. Relay 552 and relay 522 in operating cause a sender, whichotherwise might be connected to the coincontrolcircuit connected to link 580, to be connected to the coin control circuit connected to link 590, in the same manner as when thecoin control circuit connected to link 580 is busy as above described.

As soon the sender is connected to the coin control circuit, a circuit is closed from battery winding of marginal relay 002, winding of slow releasing relay 601, conductor631, contacts of relay 509, conductor 519 of horizontal link 560 of the coin control connector, contacts of relay 500, conductor 529, resistance 138, right back contact of relay 411, conductor 4:56, conductor 4:37 to ground on the middle right front contact of relay 121. Relay 601 operates in this circuit :bnt relay 602 which is marginal fails to operate due to the fact that resistance 4138 is in the circuit. Relay 001 in operating closes circuits for relays 003 and 604:.

The circuit for energizing relay 03 may be traced from battery, winding of relay (303 right back contact of relay 605. conductor ('3'? to ground on the front contactio't relay ($01. Relay (504; is operated in a circuit from battery, lelt winding of relay 001, left back contact of-relay (305, left back contact of relay (SOG, right back contact of relay (305, conductor 637 to ground on the front contact of 40 i lay 612 operates and prepares a circuit for j battery, Winding of relay 601.

, permitting Relay 604 operates and at its inner right front contact prepares a locking circuit for itself. 1

As soon as relay 601 operates, time measuring circuits'are established whereupon at the end of a definite interval of time, during which the preliminarycoin test will have taken place, relay 605 is operated thereby the sender to complete or to continue to arrest the establishment of the talking connection depending upon whether or not the coin has been deposited in the coin box. The foregoing operation is described in detail as follows: i

. lVit-h relay 601 operated, a circuit is completed for energizing pick-up relay 610-from relay 610, contact 640 of interrupter 642, conductor 639, right back contact of relay 605, conductor 63? to ground on the front contact of relay 601. Relay 610 operates and locksin a circuit from battery, its right front contact, conductor 639 to ground as previously described. 'Upon the closure of interrupter contact 641, a circuit is completed for operating relay 611 from battery, Winding of relay 611, back contact of relay 612, left front contact of relay 610, interrupter contact 641, conductor 639 to ground on the front contact of relay 601. Relay 611 operates and completes a holding circuit for itself from battery through its Winding, Winding of relay 612, left front contact of relay 611, conductor 645, conductor 639 to ground on the front contact of relay 601. Relay 612 doesnot operate in this circuit at this time since the circuit through relay 612 is shunted through contact 641 of interrupter 642. When interrupter contact 641 opens, the shunt around the winding of relay 612 is removed and re energizing relay 613 upon the next closure of interrupter contact 641. l/Vhen contact 641 again closes, relay 613 operates in a cir- 'cuit from battery, back contact of relay 614,

front contact of relay 6l2,left front contact of relay 610, interrupter contact 641,

conductor 639 to ground on the front contact of relay 601, and completes a'. holding circuit for itself from battery, through its Winding and the winding of relay 614 in series, its left front contact, conductor 645, conductor 639 to ground on the front contact of relay 601. Relay 614 does not oper- 1 ate at this time since it is shunted through the contact 641 of 'interrupter 642. l/Vhen interrupter contact 64.1 again opens the shunt around relay 614 is removed and re lay 614 operates, and in so doing prepares a circuit for operating relay 615. Upon the next closure of the interrupter contact 641,

a circuit is completed for energizing relay 615 from battery, rightback contact of relay-616, front contact of relay 614, front contact of relay 612,- left front contact of prepares at its front contact back relay 610, interrupter contact 641, conductor 639 to ground on the front contact of relay 601. Relay 615 operates and completes a operating relay 605.

of interrupter contact pleted from battery,

front contacts of relays 616, 614 and 612 in series, left front contact of relay 610, interrupter contact 641, conductor 639 outer right back contact of relay 605 to ground on the front contact of relay 601. Relay 605 operates and closes its outer right front contact before it opens its right back contact so that a circuit for locking relay 605 is completed from battery, winding and outer right front contact of relay 605, conductor 637 to ground on the front contact of relay 601 before the initial energizing circuit for operating relay 605 is opened at its right back contact. Relay 605 in operating also opens atits left contact the initial energizing circuit of relay 604. 1

During and before the expiration -of the interval of time measured by the operation of the counting relays and before the operation of relay 605 which has just been described, a test circuit will have been completed and Will have made a test of the ealling subscribers line to determine Whether the calling subscriber has deposited the proper coin or not.

l/Vith relay 603 operated, a circuit is com pleted for making a preliminary test of the calling subscribers line for the proper coin Winding of relay605,

.relay 616 is from a 110 Volt negative battery source,

right-front contact of relay 603, conductor 651, left back contact of relay 609, conductor 652', through the right wimling of marginal relay 617, outer right back contact of relay 607, intermediate winding of relay 618, conductor 653, outer right back contact of relay 629, conductor 654, contact of relay 50.), conductor 518 of horizontal link 560, contact of relay 506, conductor 528, outer left front contact of relay 404, right innerback contact of relay 420, right intermediate back contact of relay 403, conductor 441, contacts and horizontal link 375 of sender selector switch 300, conductor 358, conductor 13. contacts and horizontal link of line switch 25, conductor 9, substation 10, conductor 8, contacts and horizontal of line switch 25,0011- ductor 12, conductor 357, contacts and horizontal 375 of sender selector switch 300, conductor a l-2, outer right back contact of relay 103, outer right back contact of rela}' 4e20, inner left front contact of relay -l0-i, conductor 5L7, contactof relay 506, conductor 517 of horizontal link 560, contact of relay 509, conductor 655, inner right back contact of relay 629, conductor 656, leftwinding of relay 618, inner right back con tact of relay 607, left winding of relay 617 to ground through the resistance Relay 618 operates in the foregoing circuit, but marginal relay 617 does not operate because of the presence of resistance in this circuit. 7 However, if there is a coin in the coin-box or a ground improperly on the line, a circuit shunting the resistance will be completed either through the windings of coin'collect magnet 15 to ground 16 through the contacts 17 closed by a deposited coin or to ground improperly on the line as the case may be causing marginal relay 617 to operate. Therefore, it is to be observed that if relay 617 does not operate, it indicates that the calling subscriber has failed to deposit a coin in the coin box and that the line is not improperly grounded. Coin magnet 15 is not operated in the above circuits as the current is-not of sufficientstrength to operate it.

hen relay 617 operates, it completes a locking circuit for itself from the source of negative potential through its right winding as described, its inner right front contact, conductor 657 to ground on the front contact of relay 601. Vith relay 617 operated, a circuit is completed foroperating relay 607 from battery, right front contact of relay 617, winding of relay 607 to ground on the front contact of relay 601. Relay 607 operates and at its right front contacts transfers the subscribers loop from the windings of relay 617, through the left and intermediate windings of relay 610 to test for a direct ground at the coin box. This circuit may be traced from source of negative battery, right front contact of relay 603, conductor 651, left back contact of relay 600, conductor 652, middle winding of relay 610, outer right front contact of relay 607 intermediate winding of relay 619, conductor 653, outer right back contact of relay 620, conductor 654, thence as previously described, conductor 655, inner back contact of relay 620, conductor 656, left winding of relay 618, inner right front contact of relay 607, left winding of relay 610, to ground through the back contact of relay 619 and the con act of relay 601. Relay 619 is designed to operate in a circuit with only a comparatively small resistance and is unable to operate through the resistance of the coin collect magnet windings.

If there is, therefore, a direct ground improperly on the line, relay 619 will operate and provide a locking circuit for relay 60 1- which may be traced from battery, right winding and right front contact of relay 604i, conductor 658, right front contact of relay 619, conductor 657 to ground on the front contact of relay 601. Relay 610 in operating also removes the shunt around its right winding including this winding in series with its left winding. If the coin has been deposited and there is no direct ground on the line, relay 610 will not operate and consequently a holding circuit will not be provided for holding relay e01 operated after its initial energizing circuit through its left winding is opened at the left back contact of relay 605 which operates, as previously described, upon the expiration of the time measured by the counting relays. Relay 60% will thereupon deenergize.

It should be observed at this time that the sender has not succeeded in establishing the connection beyond the release of the district marker because the energizing circuit. through the right back contact of relay 106 and the left front contact of relay ill for operating the line marker sender connector for attaching a line marker to the sender, as described and illustrated in-the aforesaid patentto S. B. lVilliams, is held open at the left front contact of unoperated relay 411. it is obvious that until relay 411 is operated, the talking connection cannot be extended to the called subscribefis line.

Assuming that the calling subscriber has deposited the proper coin in the coin box, relays 618, 617 and 607 will have operated so that the circuit through the right winding of relay 604: is opened at the left back contact of relay 607. At the expiration of the period of time measured by the counting relays, relay 605 is operated and opens the energizing circuit of relay 60-1 causing it to deenergize. Relay 605 in operating discounects ground at its outer rightback contact from conductor 630. thereby causing the deenergization of the counting relays 611, 612, 613. 61 t, 615, 616 and relay 610 and 603.

Vith relay 60% deenergized a circuit is complet d for energizing relay ill in the sender. lhis circuit may be traced from battery, winding of relay 4'11, outer hack contact of relay e08, conductor 52a, contact of relay 506, conductor 514. of horizontal link 560, contact of relay 509. conductor 650,0uter left back contactof relay 6'21, inner left back contact of relay 601-, inner leftback contact of relay 608. outer left back contact of relay 616, inner right front contact of relay 605 to ground on front contact of relay 601. Relay 411 operates and in so doing establishes a circuit, as described in the aforesaid patent to S. B. lVilliams, for initiating the operation of the line marker. This circuit may be traced from ground on the inner leftcontact of relay 4-21, outer left back contact of relay 103, front contact of units register relay 927, back contact of relay 424, front contact of district marker release relay 425,

back contacts of relays 418, 409, 410 and 427 in series, left front contact of relay 407, left front contact of relay 411, right back contact of relay 406, conductor 455 to grounded battery in the sender register circuit (not shown).

The operation of the line marker completes the establishment of the connection to the called subscribers line whereupon ringing current is placed on the called subscribers line in a mannerwell known in the art and described in the aforesaid patent to S. B. lVilliams.

Assuming that the preliminary coin test is satisfactory and that relay 411 is operated as previously described the energizing circuit for relay 404 is opened at the inner left contact of relay 411. Relay 404 releases and at its right front contact opens the energizing circuit of relays 501 and502. Relay 501 releases and in so doing opens at its right front contact the energizing circuits for relays 506, 521 and 523. Relay 506 releases and disconnects the sender from the horizontal link circuit 560. Relay 523 deenergizes and releases relays 522 and 552. The

' have been released and that coin control connector group G, is in condition to again per mit the coin connector switch circuit to connect a coin control circuit to the sender which next causes the operation of a start relay in group G andthat coin control circuit 600 is again idle and free to be. connected to a sender.

\Vhen relay 411 operated it opened atits right back contact the energizing circuit for relay 601. Relay 601 releases and opens the energizing circuits for gelays 605, 607 and 617 all of which release. Vhen relay 404 releases it opens at its inner and outer left front contacts the connection between the line loop and the windings of relay 618 causing the latter to deenergize and at its middle left front contact opens the holding circuit of relay 401. It will be observed that all operated relays in the coin control circuit have now been released.

After the line marker has been disconnected from the sender relay 406 is operated as described in the aforesaid patent to S. B. Williams. Relay 406 inoperating completes a circuit for operating sender release relay 403. This circuit may betraced from battery, left winding of relay 403, conductor 663, left back contact of stations register control relay 1013 in "the sender register, rightfront contact of relay 406, the inner left front contact of relay 411, left front contact of relay 407,

of relays 409 and 418, left front contact of relay 425, back contact of relay 424, front contact of units register control relay 927 in the sender register, innermost right back contact of relay 403 to ground on the inner left .front contact of relay 421. Relay 403 operates and completes a locking circuit for back contact of relay 427, back contact of relay 410, back contacts itself overits front contact to ground on the middle right front contact of relay 421, and its right hand back contacts open the initial energizing circuit of relay 403 and the circuit including the calling subscribers line and the impulse relay 401 which releases. It

is to be noted that relay 403 in operating closes its front contact before opening its innermost right back contact thereby completing a locking circuit for itself before opening the initial energizing circuit. Relay 403 in operating also opens at its left back contact the holding circuit of relay 421. Upon the release of pulsingrelay 401 slow release relay 423 releases and opens the initial energizing circuit of relay 421. Relay I 421 is therefore released at this time causing ground potential to be removed from the various holding conductors thereby causing all the relays in the recording sender to deenergize and release.

-When relays 423 and 403 release, the holding circuit of horizontal magnet 306 of the sender selector switch 300 is opened at the outer right front contact of'relay 423 and the left back contact of relay 403. Horizontal magnet 306 releases and in so doing restores its associated horizontal rod sothat the recording sender is disconnected from the district selector circuit and returned to normal. The release of relays 403 and 423 also opens the energizing circuit of relay 101. \Vhen relay 101 releases it opens the energizing circuit for slow release relay 112. Slow release relay 112 however remains operated for a short interval of time. During the interval in which relay 112 is releasing a circuit is completed for operating relay 103 from battery, left front contact of relay 112, winding of relay 1.03, outer right back contact of relay 104, inner right back contact of relay 101 to ground on the left front contact of relay 102. Relay 103 operates and completes a locking circuit for itself from battery, inner left front contact of relay 103 to ground over thecircuit just described.

When relay 112 releases it opens the energizmg circuit of relay 102. However, since relay 102 is also a slow release relay it holds its armatures attracted for a short interval of time. During the interval of time within which relays 112 and 102 are releasing, relay 103 is held operated in a circuit to ground on the left front contact of relay 102. lVith relay 103 operated, a circuit is completed for operating supervisory relay 113 from battery, lower right winding of repeating coil 160, winding of relay 113 inner left back contact of relay 101, conductor 13 over the ring side of the line to the calling subscribers station 10, back over the tip side of the line, conductor 12, outer left back contact of relay 101, inner left back contact of relay 104, outer right front contact of relay 103 to ground through the lower leftwinding of repeating coil 100. Relay 113 operates and completes an obvious circuit for holding relay 112 energized. Relays 112 and 102 are made slow releasing so as to allow sufficient time for relay 113 to operate and reenergize relay 112 which in turn reenergizes relay 102 before it releases since it is obvious that if relay 102 should release its armature, ground on its front contact for holding the line switch, the district selector switch and the subsequent train of switches would be disconnected, the foregoing switches released and connection disestablished.

Relays 112 and 102 are now held under the control of relay 113 and the calling subscribers switchhook. Relay 102 maintains ground potential on sleeve conductor 11 to hold operated the line switch, district selector switch, and the subsequent train of switches, as disclosed in the aforesaid patent to S. B. Williams.

Relay 103 in operating also provides supervision over the called subseribers line. Assuming that the call was routed for example to a call indicator of local mechanical office, relay 105 or relay 106 is operated accordingly. If the called subscriber is situated in a call indicator office, relay 105 is operated in acircuit from battery, through its winding, lead 11%? to a ground in a district marker (not shown) as described in the aforesaid patent to S. B. \Villiams. Relay 105 in operating prepares at its inner left front contact and outer left front contact the circuit for including polarized relay 107 in a. circuit over the called subscribers line. When the called subscriber in the call indicator office answers, current flowing through relay 107 is reversed. thereby operating polarized relay 107. If relay 107 remains steadily operated, a circuit is completed for operating relay 109 under the con trol of interrupter contact 133. This circuit may be traced from battery, on the outer left front contact of relay 103, right front contact of relay 107, right back contact of relay 108, winding of relay 109, right back contact of relay 109, interrupter contact 133 to ground. Relay 109 operates and at its inner right hand arn'iature completes a locking circuit for itself before this armature opens the initial energizing circuit. When interrupter contact 131 next closes a circuit is completed for energizing charging relay 103 from battery winding of relay 108, outer right front contact of relay 109 to ground through the closed interrupter contact 131. Relay 108 operates and completes a locking circuit for itself from battery, through its winding and inner left front contact, inner right front contact of relay 103 to ground on the front contact of relay 102. Relay 108 in operating opens the energizing circuit of relay 109, thereby releasing relay 109. The operation of relay 10S prepares a circuit to be hereinafter described for collecting the coin at the end of the conversation.

If the called subscriber is situated in the local mechanical office. when the called subscriber, for example the subscriber at station 700, answers a circuit is completed from battery through the winding of relay 100. left back contact of relay 105, upper left winding of repeating coil 160, ring side of trunk 130 returning over tip side of trunk 130, middle right front contact of relay 103, upper right winding of repeating coil 100 to ground on the outer left back contact of relay 105. Relay 106 operates in this circuit and completes a circuit similar to that described. above for operating relay 109 except that the path is through the front contact of relay 106 instead of the front contact of polarized relay 107. Relay 108 in the same manner, as described above, operates to prepare a circuit for collecting the coin at the end of the conversation and releases relay 109.

After the conversation is terminated and the calling subscriber has replaced his receiver on the switchhook, the circuit for energizing supervisory relay 113 is opened at the calling subscribers station. releasing relay 113. Relay 113 in releasing opens the energizing circuit of relay 112. Relay 112 releases and opens the circuit for slow release relay 102 which. remains operated for a short interval of time thereafter. lit'fOi'P relay 102 releases, a circuit is completed from battery, inner left front contact of relay 103, left winding of relay 110 to ground on the right l lCli contact of relay 112. Relay 110 operates and innrediately completes a circuit for operating relays 31 l. and 201. This circuit may be traced from battery, winding of relay 311. conductor winding of relay 201, conductor 1'23, outer left front contact of relay 110, conductor 14:1, inner right back contact of relay 101 to ground on the left front contact of relay 102. Relay 2-01 operates and closes a circuit for reenergizing relay 102 before it can release. This circuit may be named from relay 201. Relay 201 in operating completes a holding circuit foritself and relay 311 over its inner left front contact, conductor 124,

inner right, back contact, of relay 1-01 to ground on the front contact of relay 102.

The operation of relay 311 at this time H completes a circuit for selecting a special sender arranged not to register pulses but to collector return the coin. Relay 311 in operating causes-sender vertical magnet 325 to operate in thesame manner as previously described for the selection of a recording sender. When the horizontal group relay 210 and the verticalgroup relay 314 operate, circuits are completed for operating relays 223 and 207 respectively. The circuit for. operating relay 223 may be traced from battery, winding of relay 223, conductor 23.6, outer left front contact of relay 314, conductor 228, front contact of relay 225 to ground on the inner back contact of relay 224, and the circuit for operating relay 207 may be traced from battery, winding of relay 207 to ground on the outer left front contact of relay 210. Relays 223 and 207 are quick acting relays and will complete a circuit for 1 energizing relay 315 before the sender vernet 331. and connects the district selector tical magnet 325 operates and closes its front contacts. This circuit may be traced from battery, winding of relay 315, conductor 323, link conductor 237, uppermost closed contact of relay 223, conductor 238, innermost right front contact of relay 207, middle rightffront contact ofrelay 201, conductor 132 to ground on the inner left front contact, of relay 110. Relay 315 in operating completes a circuit for energizing trunk vertical magnet- 331. It is to be notedthat relay 315 determines the selection ofeither a recording sender or a coin controlfconnecting circuit dependent upon whether relay 315 is in an unoperated or operated condition, respectively.

Trunk vertical magnet. 331 in operating prepares the contacts controlled by the vertical rod associated with magnet 331 for connection with the conductors of horizontal link 37 5. Trunk vertical magnet 331 in operating also completes, at its lower aniddle front contact a circuit foroperating horizontal magnet 306. This circuit may be traced from battery, right winding of horizontal magnet 306, left back contact of horizontal relay 217, right front contact of horizontal group relay 210, back contacts'of other horizontal group relays 211 and 212 in series, conductor 235, lower front contact of sender vertical magnet 325 to ground on the lower middle front contact of vertical. mag- Horizontal magnet 306 operates circuit 100 to the special coin sender 4'50.

Withvdistrict selector circuitlOO connected to special coin sender450a circuit is com I pleted for operating holding relay. 451 from relay 451, conductor 452 lowest front contact of battery, winding of to ground on the trunk vertical magnet 331. Relay 451 op crates and itself from inner right front contact to ground on the back contact of release relay 435. After horizontal I magnet 306 operates, vertical magnets 325 and 331 release as previously described. ground on the back Contact of release relay 435 to conductor 452 through the inner right front contact of relay 451 for holding l1orizontal magnet 306 and relay 217 operated after the release of vertical magnet 331. The vertical group and horizontal group relays and their associated relays are deenergized in the same manner as when a recording sender is connected to the line. When trunk vertical magnet 3310perated,

completes a locking circuit for battery through its winding and Relay 451 in operating connects a circuit was also completed for operating front contact of trunk vertical magnet 331.

Relay 101 is held operated after the release of magnet 331, in a circuit over conductor 452, right front contact of relay 451 to ground at release relay 43,5. Upon the operation of trunk vertical magnet 331, a circuit for holding relay 110 operated was also completed from battery, right Winding and inner right front contact of relay 110, conductor 359 to ground on the lowermost front contact of magnet 331, andafter the release of magnet 331, the holding circuit for relay 110 is completed over conductor 452, inner right front contact of relay 451 to holding ground on the back contact of relay 435.

rRelay 111 is now energized in a circuit from battery, left winding of relay 111, inner right front contact of relay 110, conductor 359 to ground, as previously described. Relay 111 operates and completes a locking circuit for itself from battery, right winding and right front contact of relay 111, conductor 359 to ground, as previously de scribed. Belay 111 in operating provides an additional holding circuit for relay 108 traceable from battery, winding and inner left front contact of relay 108. inner left front contact of relay 111 to ground on the inner'back contact the energizing circuits of relays 201 and 311 which release. Relay 201 in releasing opens the energizing circuit of relay 102 at its outer left front contact. Since relay 102 is a slow releasing relay, the operation of relay 101 will complete a new energizing circuit for relay 102 from battery, winding of relay 102, outer left front contact of relay 111, right front contact of relay 101 to ground on the front contact of relay 102 before relay 102 can release. Relay 101 in operating opens at its inner right back contact the energizing circuit of relay 103 which deenergizes. Relay 103 in deenergizing opens at its inner left front contact the initial energizing circuit for relay 110. Relay 110 does not deenergize since it is held operated over its right winding and right front contact as previously described. The release of relay 103 opens the holding circuit of relay 108. Relay 108 does not deenergize at this time since it is held operated in a circuit through its inner left front contact and the inner left front contact of relay 111.

\Vhen relay 451 operates, it completes a circuit for energizing a start relay in a coin control connector associated with the selected special coin sender 450. This circuit may be traced from battery, back contact of non-interfering relay 501, right winding of start relay 503, conductor 520 to ground on the outer right front contact of relay 151. Relay 503 operates and causes .the coin control connector to operate and attach an idle coin control circuit to the special coin sender 450 in the same manner as previously described for connecting a coin control circuit to a recording sender for preliminary coin test.

The start relays, such as relay 503, associated with the special coin senders, since they are independent of the start relays associated with the recording senders, may be included in a start relay group including start relays individual to recording senders, as shown in this case, or they may be arranged in a separate start relay group with access to a sufficient number of coin control circuits.

\Vhen the coin control circuit is attached to the special sender 150, a circuit is completed for operating relay 606. This circuit may be traced from battery, winding of relay 606, conductor 622, contacts of relays 507 and 509 and lead 516 of horizontal link conductor 546, to ground on the outer right front contact of relay 151. A circuit is also completed from battery, winding of marginal relay 602, winding of relay 601, conductor 631, contact of multi-contact relay 509, lead 519 of horizontal link 560, contact of multi contact relay, conductor 519, contacts and lead of horizontal link 3T5, conductor 353, outer right front contact of relay 110, inner left front contact of relay 108, inner left front contact of relay 111 to ground on the left front contact of relay 102. Relays 601. and 602 operate in this circuit. The marginal relay 602 operates in this circuit since the circuit does not include the resistance 436.

With relays 601 and 606 operated, a circuit is completed for operating relays 629 and 609 from battery, windings of relays 629 and 609 in series, inner back contact of relay 616, outer right back contact of relay 604-, left front contact of relay 606, outer right back contact of relay 605, conductor 63?, to ground on the front contact of relay 601. Relay 609 operates and completes at its outer left front contact a holding circuit for relays 609 and 629. \Vith relays 629 and 609 operated a circuit is completed for operating relay 608 from battery, left front contact of relay 629 to ground on the outer left front contact of relay 609. Relay 608 operates and completes an obvious locking circuit for itself. Relay 601 in operating also completes a circuit for operating relay 603 from battery through the winding of relay 603, outer right back contact of relay 605 to ground on the front contact of relay 601.

When relay 601 is operated a circuit is prepared for starting the operation of the time counting relays. Upon the closure of interrupter contact 6410 a circuit is completed for energizing relay 610. This circuit may be traced from battery, winding of relay 610, back contact of relay 610, interrupter contact 6-10, outer back contact of relay 605 to ground on the front contact of relay 601. Relay 610 operates and completes a locking circuit for itself from battery, through its windirfg and right front contact to ground as previously described. Upon the subsequent closure of contact 641, a circuit is completed from battery, winding of relay 611, back contact of relay 612, left front contact of relay 610, interrupter contact 641 to ground, as previously described. Relay 611 operates and at its left front contact prepares a circuit for operating relay 612 and for holding itself energized upon the opening of interrupter contact 641 in the same manner as hereinbefore described.

\Vith relay 611 operated 110 volts positive battery potential is connected to the tip and ring sides of the calling subscribers line. 110 volts positive battery potential is connected over the tip side of the line from 110 volts positive battery source, left front contact of relay 603, outer right contact of relay 602, inner right front contact of relay 611 inner right back contact of relay 613, inner right back contact of relay 615, inner right front contact of relay 629, conductor 655, contact of vertical relay 509, lead 517 of horizontal link 560, contact of vertical rclay 507, conductor 547, contacts and horizontal link 375 of switch 300 conductor 357, to conductor 12 on the tip side of the calling subscribers line, windings of polarized coin collectmagnet 15, contacts 17 to ground 16. Current is in such a direction through the magnet 16 as to cause it to operate to collect the deposited coin in a manner well known 

